this action succeeds when this channel becomes readable. Next read() should see some bytes.

this action fails due to cancellation, channel being closed, server shutdown, etc.

if parameter `accepting==true`, and the server is/becomes in the state
of acceptingPaused/Stopped,
this action fails with a message that the server is not accepting new connections.
This is useful, for example, for an HTTP server to await for a new http request on a persistent connection;
if pause/stopAccepting() is called, the pending awaitReadable actions fail, achieving the effect
of not only pause/stop accepting new connections, but new requests as well.